NEW YORK— In his speech to the United Nations General Assembly Tuesday, President Barack Obama will address overtures from Iran, steps to eliminate Syrian chemical weapons, and Israel-Palestinian peace talks.

Obama is expected to speak directly to world leaders about recent Iranian overtures, and on Syria about what he sees as the world's responsibility to firmly oppose the use of chemical weapons.

But White House officials say he also intends to speak about how the U.S. sees events and complex challenges in the Middle East and North Africa, including the situation in Syria, and how these relate to U.S. interests.

At an event Monday discussing global challenges to civil society, Obama provided a possible preview of what he may say about what he called “convulsions” in the Arab world.

He said they are a reminder that change is “not always a smooth path” but is something the United States is committed to.

“I want to affirm that over the long run, we will all be better off if that small shopkeeper or that small farmer or that young student or that disabled person or that gay or lesbian person or that ethnic minority or that religious minority, if they have a voice and their dignity is respected, that is what will preserve our dignity and that is what will preserve our security over the long term,” Obama said.

On Syria, the White House has said Obama will call for the international community to take a firm position against the use of chemical weapons.

He also will urge leaders to support a U.N. Security Council resolution to enforce consequences if the Bashar al-Assad government fails to cooperate with steps to bring Syrian chemical stockpiles under international control.

As for hopes of a possible thaw in U.S.-Iranian relations, amid overtures by Iranian President Hasan Rouhani, White House officials continue to say that no meeting is scheduled.

Iran will hold talks with the P5+1 group of nations, including the United States, this week in New York.

Deputy National Security Adviser Ben Rhodes said no single meeting or encounter will solve all issues between the U.S. and Iran, but that the U.S. remains open to engagement.

"The issues between the United States and Iran are not ones that would be settled in any one discussion and there [are] longstanding differences, particularly related to the nuclear program," he said.

The Iranian leader addresses the General Assembly session Tuesday after Obama speaks to world leaders. Rouhani has recently said Iran has no intention to develop nuclear weapons.

There was new pressure Monday on Obama from key Republican and Democratic senators, who urged him use his speech to state again that Iran will not be allowed to develop a nuclear weapon.

The president also will also use his speech to take note of the direct talks Israel and Palestinians are holding on final status issues and opportunities these present.

On Tuesday, Obama meets Palestinian President Mahmoud Abbas on the sidelines of the General Assembly session. He meets with Israeli Prime Minister Benjamin Netanyahu at the White House on September 30.

The president also meets with Lebanon's President Michel Suleiman, focusing on challenges Lebanon is facing from thousands of refugees from Syria and support for Lebanon's democratic process.

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